We are a commune of inquiring, skeptical, politically centrist, capitalist, anglophile, traditionalist New England Yankee humans, humanoids, and animals with many interests beyond and above politics. Each of us has had a high-school education (or GED), but all had ADD so didn't pay attention very well, especially the dogs. Each one of us does "try my best to be just like I am," and none of us enjoys working for others, including for Maggie, from whom we receive neither a nickel nor a dime. Freedom from nags, cranks, government, do-gooders, control-freaks and idiots is all that we ask for.
An athletic friend who is around my age was saying that he ought to begin weight training. He never has tried it, but nobody likes the effects (or the sight) of lost muscle mass.
Experienced trainers can work with you on endurance, agility, balance, strength, cardio, general conditioning - whatever you want. So the first question he or she should ask you, on a first meeting, is your goals. You can even mention weight loss if that is a goal, in which case a trainer will offer advice on a nutritional plan. (An honest trainer, though, will tell you that exercise is only an adjunct to appropriate nutrition, not a substitute.)
Second thing the new trainer should run through is medical history and active medical issues. You might be asked to get a cardiac stress test, or other check-ups.
The third thing a new trainer will do is to run you through a number of exercises to assess your condition. They like to get a baseline. These exercises will check your endurance, cardio fitness, upper and lower body strength, balance, etc. You just do your best, no matter how lame it is.
The fourth thing a trainer will do is to recommend a plan for you. In my case, it has been 2 days of weights with him, 2 days or calisthenics recommended by him, and 2 days of HIIT cardio. One of these days I will cut him back to 1 day/wk for the weights I am not comfortable doing alone, like barbell squats, bench press. Even if you exercise on your own, it is a good idea to learn the right technique for everything. There is even a right and wrong way to do something as simple as Jump Rope, or Farmers' Walk: